Leak alarms aren't new, but in the past they were often expensive and rarely user-friendly. Enter the WallyHome Water Sensing System, a suite of gizmos that make leak detection more affordable and more effective. How? Traditional leak detectors just make noise (albeit a loud one) when triggered. The problem is that you may not be home every time a leak occurs. WallyHome keeps you in the loop: The instant one of its sensors detects an issue (either moisture or a dramatic change in temperature or humidity), Wally sends a notification right to your smartphone. Available on Amazon; $299.